Piston packing-bing



- ferred to are known in which the opposite UNITED sfrArEs PATENT oEEIoE.

JULIUs E GGERs, oreAssEL WILHELMSEHE, GERMANY, AssrGNoR, BY MESNE ASSIGN- MENTS, rro LocoMoTIvE SUEEEHEATER COMPANY, A CORPORATION or DELAWARE.

PIs'roN PACKING-RING.

Application led June 2, 1915, Serial No. 31,794.

17 o all lwhom it may concern Be it known that I, JULiUs EGGERS, a citizen of the German Empire, residing at CasselV lVilhelmshhe, Germany, have invented' a certain newand useful Improvement in Piston Packing-Rings, of which the following is a specification.

My invention relates to an improved piston packing ring of the elastic or self-adjusting type adapted to lie in an annular recess of the piston and provided Awith inwardly projectixw hooked ends arranged to enga-ge suitably Formed recesses in the bottom Aof the annular ring.

In the prior art rings of the kind just refaees of the hooks, which faces engage the surfaces of the recesses in theyannular ring, are portions of substantially radial' planes or ot' planes parallel with a piston diameter.v With such a construction when the piston and ring are removed from the en gine cylinder there is nothing to prevent the piston ring 'hooks becoming unseated and the ring released from the piston should said ring happen to be pushed into the bottom of the annular recess on the side opposite the hooks. K

It is the purpose of the present invention to do away with the disadvantage above set forth by providing the body ot' the piston with undercut (notched) grooves or the equivalent and the ends of the piston ring with correspondingr hooks or projections which engage said notches sodas to limit the expansion of the ring and secure it in position without holding it rigidly. If the f ring is slipped overt-he piston by expanding it to a diameter somewhat greater than the inside diameter of the cylinder, the end hooks, under the infiuence of the elasticity of the ring, will automatically slip into the notches from which they cannot be dislodged except by forcing 'the ends of the ring together and then displacing the entire ring radially by pressnre'upon the side opposite the hooks.

If, in the course of time, the wear on the running surface of the ring makes the readjustment of its expansion quality necessary, one only needs to reverse the process just described in order to remove the ring from the piston. To accomplish this. the ring is compressed to such an extent that by pushing the ring over radially across the Specification of Letters Patent.

Patented Nov. 1S, 1919.

Renewed August 8, 1919. Serial No. 316,181.

piston, the hooks will slip out ot' the grooves and the ring may then be taken out of the piston in the usual manner.

- further degree of expansion desired.

The hooks or projections may either be placed at the extreme ends of the ringor, if desired, at some. other convenient point on the inner circumference of the ring.

My invention wil-1 be better understood by referringr to the accompanying drawing in which Figure 1 shows a part of the piston in axial longitudinal section; Fig. 2 shows a Vpartial cross section thereof; and Fig. 3 a cross section of the entire piston on a reduced scale.

In the drawing the piston is one of a usual type. It comprises an annular shell a which-1s removably fastened to the pis- 'ton body I; by screws c and is provided with three .annular recesses or grooves d for the reception of the piston rings e; these rings have their abutting ends displayed with reference to. one another as usual. The ends of each ring, at the joint f, are providedwith two inwardly projecting hooks or noses g which engage corresponding und ir-cut notches k in the rin or shell a. These notches h, in the'embodlment represented, are formed in a special insert piece z', for purposes of convenience in manufacture, which is removably fastened to the shell a by screws k. A s shown in the figures, the piston is in its cylinder and the ring is fitted so that it is able to expand and contract with variations in diameter of said cylinder. The ring is securely held in position by means of the'hooks g which cannot escape from the notches h but which in no way lessen the elasticity of the ring necessary for the smooth running of the machine,

since the same can be pressed .together by an amount corresponding' to the seniration of its ends. As weer on the run?. surface of the ring n continues, the space l etween the hooks g and the correspomlmg surfaces of the notches l1. becomes smaller until finally the hooks will lie directly uponI the notches so that hooks and end surfacesare pressed together. It' any leakage' takes place with further running of the machine one needs only to tile away the engaging surfaces ot' the hooks or ot the notches sui- Iiciertly tfpermit the further desired expansion e! the ring. 'lo accon'iplish this the 'ring ends are pressed together and the entire ring pushed over from the opposite side of the piston so as to free the hooks from the notches.

The rings may be made eccentric in the usual manner for the purpose ot' securing greater strength andelasticity. In this case the grooves, in order to properly take in the rings, must lie-deepened corresponding to the eccentricity. The rings will have their greatest thickness and tension opposite the notches h. The use of such eccentric rings provided with hooked ends does not entail any special difficulties. In making them by means ot va milling machine c. y., the outer circumference is first prepared and then the ring is suitably dis'- placed radially with reference to the ring and the inner circumference prepared. Finally the hooks themselves may be formed.

The invention is obviously not limited to the embodiment represented. The notches in the piston body and the hooks or projections on the piston rings may have any preferred undercut or equivalent form and as previously mentioned,may-be placed at any desired position upon the inner circumference ot the ring.

Having described my invention, I claim:

1. In'an engine, the combination of a piston having an annular recess, there being formed in the bottom of said recess a second recess having oppositely undercut ends, and an elastic piston ring in the first recess having ends provided with hooks complementary to and adapted to engage said undercut ends, the peripheral distance between the points of the honk when the ring ends are pressed together being less than the periplren eral distance between the points oi' the undercut ends and the diameter of the piston at the bottom ot the recess being substantially less than the inner diameter of the ring when compressed to a degree such that e5 the distance between the points of the hooked ends is just barely less than the tance between the points o; he undercut ends ot' said second recess.

2. In an engine.y the combination of a piston having an annular recess, a detachable but normally fixed insert piece fitted into the. bottom ot' said recess said piece being itself' provide-d with a recess .having oppositely undercut ends, and a split elastic pise5 ton ring in the first recess provided with hooks` complementary to and adaptedV to engage with the undercut ends of the insert piece.

3. In a piston, in combination, a spring packing ring having a dovetailed projection upon its inner side, said ring being divided; through said projection and the two ends! thus formed being normally separated cir- (nmferentially but adapted to lbe mutually1 75 approached by compressing the ring and a lock piece fixed in the piston bodyl opposite the dovetailed projection, said lock piece having a recess the form of which is complementary to the dovetailed' projection, the 80 dimensions ot the piston body, ring,.and recess, being such that the recessI will admit the projection when the ring compressed and retain the ringin position when theA ring is permitted to expand as and for the purpose described.

In testimony whereof I have hereunto set my hand in the presence of tivo subscribing witnesses.

JULIUS EGGERQ.

l'lf'itnesses:

J ULLUS Fiemme, CARL MOLD. 

